Numerical investigation of thrust vector performance and flow separation in clustered annular aerospike nozzles with differential throttling

Aerospike nozzles could adjust aerodynamic boundaries automatically, enabling altitude compensation under varying atmospheric conditions. This feature significantly broadens the application potential within recoverable launch platforms. Differential flow control is feasible for thrust vector during aerospike nozzle recovery. In this paper, the vector performance of differential throttling in a clustered annular aerospike nozzle is numerically investigated. The flow separation on the aerospike resulting from differential throttling is analyzed. In low nozzle pressure ratio (NPR) scenario, flow separation occurs on the surface of the aerospike. The flow separation region is observed to expand with increasing differential throttling intensity. The flow separation migrates towards the base of aerospike nozzle with the rise of NPR. The sensitivity of thrust vector performance is investigated. The results indicate that axial force is predominantly governed by NPR, while lateral force and vector performance are chiefly determined by differential throttling intensity. A decoupled factor-based approach is proposed for predicting the vector performance of clustered annular aerospike nozzles. This study aims to explore the mechanism of vector generation and vector control method on the clustered annular aerospike nozzles.